Soul Manifesto
by KittenRainbow
Summary: (AU) The war has passed. W.D. Gaster and his son Papyrus remain as the only living skeleton monsters in the Underground. As time passes, Gaster notices that Papyrus is becoming lonely and saddened. He then becomes driven to complete his greatest science experiment yet - giving Papyrus a brother to call his own. But is it easier said than done? Please read and review!
1. Chapter 1 - Prior to the War

**A/N: Hello, everyone, and welcome to a new story that is currently in the works called _Soul Manifesto_! :D It is indeed Undertale related, because I am now Undertale trash. ;P But do not worry, I will update my Mario and FNAF stories once I'm feeling up to it. I feel my work is much better when I am feeling motivated to work on stories rather than rushing on them. :n) I hope you understand. **

**Anyway, as we all know, all of my stories have some sort of AU built within them. :D This one is no exception, but it's kinda also my headcanon. Here are the notable differences from the canon storyline:**

 **1\. Sans is the younger brother in this one. Papyrus is older, and he is W.D. Gaster's biological son, while Sans was created artificially in a lab. So, in short, Dadster and Big Bro Papyrus. :D**  
 **2\. One monster year is equivalent to five human years. Keep that in mind. (For example, Papyrus is two years old in this chapter. In earth years, he's ten years old. :) Why? Because I want it to be. Just roll with it.)**

 **That's about all I have for now, but if needed, I'll edit the differences. Enough being said, I hope you all like this story! Please review, it fills me with determination to keep posting! ;P**

* * *

 _"Papyrus, dear, smile for the camera!"_

 _"Nyeh!" The two-year old skeleton smiled brightly as he waved his little arms at the camera that his mama was holding. His face had bright red tomato stains on it, and his clothes were no less cleaner. A few limp spaghetti noodle stuck to the top of his bare skull. "I smile, mama! Look, look!"_

 _"I see! You've got quite the lovely smile, dear!" Calibri laughed as she snapped a couple of photos with the camera. The sun shone brightly overhead on the mountain they lived on, making Papyrus's face shine all the brighter. Oh, what a delightful skeleton child he was. Full of happiness and energy, he was the light of Calibri and her husband's lives. He was just so pure and innocent, and never judged anyone harshly. Rather tall for a skeleton his age, but it seemed as though he would inherit his father's height._

 _Speaking of her husband..._

 _"Gaster, dear, don't you have something to give to our birthday boy?" Calibri called out. "Now that he's finished his spaghetti, I think it's time for his present!"_

 _W. D. Gaster suddenly popped into view, his arms carrying a present behind his back. His smile was stretched into a wide toothless grin. He did have two long cracks running up and down his face as a result of his younger days, but it didn't bother Papyrus or Calibri one bit. "Why, I believe I do, honey!" he said as he trotted over to Papyrus's side at the table. "It's something very special!"_

 _Papyrus put down the plate of spaghetti he was eating (it seemed as though it was the only food that he would never get tired of eating) and looked over curiously. "Present?" he exclaimed. "I want! I want!" He made grabby motions for the present that he knew was behind his father's back. He was so excited that he didn't even notice that his mother was cleaning the tomato stains off his face and his clothes._

 _Gaster held up a bony finger. "Now, now, son, what do you say when we want something?"_

 _Papyrus pulled his little arms back and pulled on a pouty face. He sat in silence for a second, trying to remember what his parents had taught him, then hesitantly said, "Please...?"_

 _"Ah, there we go! Good job, Papyrus! Here, this is for you!" Gaster grinned as he held out the small gift wrapped in orange paper with a bone pattern on it._

 _"Nyeh-heh-heh!" Papyrus giggled excited as he took the gift and immediately started tearing off the wrapping._

 _Calibri and Gaster watched as their son's eyes nearly doubled in size as he stared at what they had given him. It was a long, fluffy scarf, beautifully handmade with tiny ruffles at the end. It was made of the softest stuff Calibri could find, and the two of them crafted it together._

 _Papyrus let out an exuberant squeal as he hugged the soft material to his chest, overjoyed. "It's a scarf! It's a scarf! So fluffy!" he exclaimed. His mama always wore a green scarf of her own, and he was so happy that now he got to have one that looked just like hers, only a different color. He unraveled it and tried to put it around his neck, but only succeeded to wrap it around his head._

 _Calibri giggled. "Here, let me," she said as she took the scarf and wrapped it properly around his neck, making sure it was snug. "There you go. Now you'll be all fit for when winter comes around the corner."_

 _Papyrus seemed to have stars in his eyes. "Yay!" he gushed as he hugged the scarf to himself._

 _Gaster, always a stickler for manners, did hold his hand up with a knowing smile and say, "Now, Papyrus, what do you say to your mother?"_

 _"THANK YOU, MAMA!" the little skeleton instantly shouted out as he jumped out of his chair and hugged her tightly. Then he also reached out and hugged his father just as tightly. "Love you!"_

 _"Heh, we love you too, Papy," Gaster said as he hugged his son back. Seeing the camera on the table, he took it and held it out in front of his family. "Smile once more, everyone!"_


	2. Chapter 2 - Eradication

Humans and monsters used to co-exist in harmony. They lived together, worked together, played together, and the little ones even went to school together. All monsters and humans had souls, in the shape of hearts. Monsters' souls were usually always seen upside-down, while humans' were right-side up. Every single soul had a certain color attributed to the being, but all would turn white and crack when their life span ended.

Monsters had use of magic, which was commonplace at that time. Different-colored magic symbolized different types of magic. Some types of magic specialized in healing, others in throwing projectiles, and still others in natural elements such as water and fire. A special kind of magic was soul magic, which only a few monsters had extended knowledge and use of. Humans had very little, almost no magic. They relied more on their physical strength. But monsters never wanted to use their magic to hurt any other monster or human. The monsters were generally pacifists, they never liked to stir up violence. They held the belief that LV was not worth attaining, so they strived to settle their disputes in other peaceful ways.

Humans, on the other hand, were brute and forceful. They held the belief that gaining LV was a form of strength and power. They always wanted to be the best in everything, even if it meant resorting to physical means. They had one thing many monsters (other than boss monsters) didn't have much of - determination. Humans had such an abundance of determination flowing through their veins. It gave them the power to persist after death, and even gave some the ability to come back to life (such as breaking out of a coma). Monsters were not as determined, so once their soul turned white and cracked, that was usually the end for them. Monster souls could not last outside of their body for very long, but human souls could, and for longer periods of time.

As the generations came and went, the humans eventually became more power-hungry and judgmental. Their relationship with the pacifistic monsters slowly became strained as the humans came to believe that monsters were...simply put, monsters. Weak. Pathetic. Always looking for the easy way out. Not wanting to take chances and augment their pitiful strength.

Then, one day, everything finally collapsed and broke. The humans were angry at the monsters, and wanted nothing more to do with them. They decided that they would eradicate every monster they could find, and then lock away the rest for eternity.

The war between humans and monsters had begun.

* * *

It was a terrible war on both sides. The humans rallied up their numbers and fought with much determination. Their LV had increased many times, so they were strong - almost as strong as boss monsters. They had more HP, more ATK, and more DEF. They were cold and heartless, and took no mercy on any monster they saw.

Monsters, at first, only tried to defend themselves. They still didn't want to fight the humans, even if the humans were ruthless. They tried so hard to have the humans stop the war and be friends again, just like how it was centuries ago.

But nothing worked.

All these attempts to pacify the humans only seemed to enrage them more. They soon thought that the monsters were trying to get their guard down in order to leave them vulnerable to attacks. In retaliation, the humans then resorted to their deadliest weapon known to all - complete genocide.

It was such a horrible, horrible time. The humans went in packs, raided several villages where specific types of monsters lived, and then dusted all the monsters living there. They did it as an example to teach the rest of monsterkind a lesson. To teach them that humans would always be superior. That monsters, no matter how strong, could never amount as much.

The monsters couldn't handle this anymore. They couldn't bear to see their former friends dash their families to the ground as if they were nothing. The monsters, albeit with a heavy heart, decided to fight back.

The king of the monsters rallied up the strongest and most determined monsters (such as, but not limited to boss monsters) to form a makeshift army known as the Royal Guard. The Royal Guard would try to defend themselves first and not resort to violence, but if the humans became genocidal again, they would then fight on the offense.

As the war dragged on, the humans became more and more vicious. They continued raiding villages and dusting all the monsters they could find. They didn't care what type of monster it was, either.

* * *

Gaster remembered that agonizing, terrible day.

The day his entire race was eradicated.

It started out innocently enough. The sun was a bright ball in the slightly cloudy sky, and he was looking up some of his books for his science career. He was no boss monster, but he did have an impressive display of magic, both bone magic and even the rare soul magic. He wanted to become the Royal Scientist one day, and was thus attaining various degrees in order to achieve that dream.

Calibri had been outside, playing with their beautiful son Papyrus. Papyrus had recently turned three years old, and was as bright and energetic as any other kid. He was growing remarkably fast, though, which was amusing. Calibri often joked that Papyrus would probably reach Gaster's height when he was full grown. He still wore the scarf that his parents had given him a year ago. It surprised both Calibri and Gaster at how gently Papyrus treated that scarf. Any other baby bones would have probably gnawed it through and worn it down, but not their child. Papyrus always wore the scarf around his neck every single day, and the only time he took it off was when it had to be washed or when he had to go to sleep, since the scarf might suffocate him if he wore it. It was his most prized possession. Even now, it was still in fairly-new condition.

It was indeed a beautiful day. It couldn't have been more perfect.

...

It was an ambush.

The skeleton monsters lived on a secluded spot on the mountain. They were generally very peaceful, and were always happy to help a friend out. While they did know about the ongoing war, they decided to stay neutral. They hated fighting, even if the monsters were technically in the right. Some of the stronger skeletons did go out to assist in the war, however.

...

No one expected the humans to come blazing though, wielding their weapons, shouting obscenities.

Skeletons had an slight above-average amount of HP. Because their entire structure were bones, they were mostly durable and sturdy. Their DEF was a little low, though, since their bones could only protect their soul so much.

Gaster heard the screams.

He heard Calibri rushing into their home, carrying a frightened Papyrus in her arms. "The humans are here and attacking everyone! Quick, let's get out of here!" she called out with such terror.

Gaster remembered grabbing his books and then following his wife and child out the door, leaving everything else behind. Maybe they could slip away without the humans noticing. Maybe they could escape.

It was chaos outside. Skeletons everywhere fled for their lives, only to be dusted by the cruel humans. No one, from the baby bones to the elders, was spared. Some skeletons tried using their bone magic to set up walls in order to shield themselves. But all was in naught; the humans merely used their physical fire to torch down the homes and get beyond the bone walls. So much pain. So much screaming. _So much dust_.

...

There were no words to describe the terrible feeling that raced through Gaster's chest. Fear, anguish, anger...all of these emotions combined into one big mess that shook his very bones down to his soul. He remembered that all he wanted was to get his family to safety. Get to the forest, where it was hard for humans to navigate. Save them.

He didn't hear the arrow whizzing through the air. He only turned when he heard Calibri let out an airy gasp and fall to the ground, letting go of Papyrus. The small child fell unhurt, but then started shouting for his mom, fearing that she was hurt.

" _Calibri!_ " he remembered shouting. His eye sockets widened in absolute despair as he saw the arrow stuck neatly in the middle of Calibri's soul. The beautiful green soul that nurtured and gave life to everything around here...depleted. It was a fatal hit for skeletons - a one-hit kill.

"No, no...!" Gaster gasped as he knelt down beside her. It couldn't be. It couldn't be. Calibri couldn't die. Don't die!

"Dear, stay with me, please!" Gaster remembered his eye sockets watering with purple tears. He remembered Papyrus screaming for his mother, fearing for her safety. He tried to pick Calibri up so that he could carry her and Papyrus into the woods, but she stopped him, shaking her head.

"N-No, dear..." she said in a gentle, pained voice. She knew what was bound to happen, and so did Gaster. "Take Papyrus and run. Get away."

"I can't leave you...!" Gaster cried, feeling his own soul writhe in grief. "No - there has to be another way!"

Calibri only let out an airy gasp as her thin frame started dusting. "I-I...love you both..." she managed to whisper before her HP depleted entirely and her bones became dust. Nothing was left.

At that moment in time, Gaster knew his life had ended right then and there. The love of his life, the one skeleton he had spent his entire life with...was gone. Killed...at the hands of these humans. These humans had left his son without a mother.

These humans...no. They didn't deserve to be called that anymore.

These...these _murderers_.

Gaster abruptly stood up, carrying Papyrus and burying the little crying one's face into his chest. He didn't want his son to lay eyes on these humans, nor what he was about to do.

He could feel a dark, intense anger begin to surge from deep within him. So these humans wanted to play dirty, huh? They thought they were so strong? Okay, then. They'll see.

The human who had shot the arrow came closer to Gaster, along with a few others. They had this wild, hateful looks on their face as they reloaded their weapons, ready to shoot at the two skeletons.

"It's a beautiful day outside," Gaster suddenly called out, startling the humans into silence. "Birds are singing, flowers are blooming..."

Unbeknownst to the humans, Gaster started gathering his magic. "On days like these, people like you..."

Without any warning, a cascade of bones suddenly jutted from the ground, impaling and instantly killing the humans standing in front of him and his son. He then turned to face the rest of humans still in the village and summoned two beast-like skeleton heads, which blasted pure energy at the humans, terminating their souls completely and killing them. Not one remained alive.

Gaster heard their agonized screams, their cries of pain. How ironic that it sounded just like the skeletons they had slaughtered just bare minutes ago. He could see the red blood pouring out from their bodies. He could see their fleshy bodies squirming and twitching uncontrollably before finally settling still, their eyes rolling up, their mouths agape. Dead.

"...should be burning in hell."

* * *

Not one remained alive.

Gaster had scoured the rest of the destroyed village to look for any skeleton brethren that might have survived or escaped. He tried so hard to find at least one skeleton who had not been reduced to dust; that still had a breath of life in them. He even tried sending out various magic signals in order to detect any skeleton that may have been lucky enough to escape into the nearby woods.

But nobody came. He couldn't sense anyone else with his magic. He couldn't find a survivor.

Nothing.

...

He and Papyrus were the only two skeleton monsters left alive.

After recovering from the magic supply he had burned through, Gaster took Papyrus back to their home, which was one of the few left unscathed by the fires. They couldn't live here now. They could only salvage what they could carry, and then head to the king, who would surely know what to do.

Papyrus was eerily quiet as he went to his room and filled his bag with some of the necessities he needed, as well as a few toys. Then he grabbed a photo frame that had the once happy family smiling in the frame. He let out a shaky breath, then put it in his bag.

Gaster couldn't leave his books behind, so he brought a type of suitcase to fit the most important ones. Then he also packed clothes, food, and some hygienic products that the two of them would need.

His eyes lost their glow as he drifted over the various photo frames and belonging that belonged to Calibri. He knew it wouldn't be right to leave them here. He didn't want to leave anything behind.

But at the same time...he couldn't bring himself to take anything. Calibri...she had meant so much to him...she had been the source of his happiness from the moment they met. Taking her belongings...it nearly felt like taboo. And it felt even worse knowing that a few short hours ago, she was alive and well.

Gaster stood in silence for a while, just staring blankly at Calibri's belonging, stuck on deciding whether to take them or not. There were no tears running down his cheekbones; he was all out of tears. An empty sadness was all he had left.

He looked up as he heard a soft bone-rattling sound. Papyrus stood at the doorway, his bag all packed up. He shared a sorrowful look with Gaster, then turned his attention to Calibri's belongings, then back to Gaster, with a knowing look.

The tall skeleton sighed. "I know, Papy...but it's hard. I feel it isn't right," he said. Papyrus probably wouldn't even understand; he was only three years old.

But then again, Papyrus was brighter than most baby bones his age. He seemed to know what his daddy was saying.

The small skeleton walked up to Gaster and hugged his leg. "Don't be sad, Papa," he said in a tiny voice. "Mama won't like it."

Gaster couldn't suppress a small laugh. "Heh...you're right, Papy," he said, giving out an ever-so-small smile. "She always did say to keep our heads up, no matter what." He let out a shaky breath as he held his arms out to his son. "Come here."

Papyrus obliged, and the two shared a tight embrace that seemed to last forever. Reluctantly Gaster pulled apart from Papyrus and looked at him. "Alright then, son...let's head out. We'll have to report to the king and see what'll become of all this."


	3. Chapter 3 - Welcome Home

It was a long, treacherous journey, but Gaster and Papyrus eventually made it to the reserve where King Asgore and his wife Queen Toriel, along with a plethora of monsters, were situated. Gaster had indeed decided to bring along some of Calibri's belongings, in hopes that it would inspire him to keep going. During the journey, the two skeletons did come across some human hunters who tried to harm them, but then Gaster, fearing for his son and himself, quickly made short work of them.

He never attempted to hide or bury the bodies. No, it was better to let them sit out and rot. Let it serve as a lesson to the murderous humans who had eradicated his entire kind and dusted his beloved wife. But it did always make him curious as to why their bodies never dusted immediately upon death, as monster bodies did. Their fleshy bodies took far longer to dust; they mainly decayed first before finally decomposing.

Once they reached the monster royals, Gaster promptly reported to them that humans had raided the skeleton village and that only he and Papyrus were the sole survivors. He then asked for information about the few skeletons who had gone to assist in the war, but he guessed it shouldn't be surprising that none of them survived the tough battles either. Humans seemed to hold a special hatred for skeletons, it seemed. Because they too had skeletal structures within their fleshy bodies, they always pegged skeletons as a type of mockery against them. They also held a special hatred for any other type of monster that was humanoid or resembled a human in more than one way. So there were quite a number of bipedal monsters who were often targeted more than others.

So it was settled, then. There were no other skeleton monsters left in the world, as far as he knew.

But he wasn't the only one with the same problem. As time went on, more and more monsters returned to home base, often with tears in their eyes as they reported that either they or a single handful of species was left alive. Grass monsters were scarce, since the humans had discovered that they were susceptible to fire. The fish monsters only had a few left, with one of them being the Captain of the Royal Guard. She had all but a single newborn guppy remaining out of fifty, since the humans had discovered her nest and destroyed the rest. The captain claimed that her guppy would soon grow up to be the most determined out of all monsters, and would be the true heroine who would crush the human race. As of such, the guppy was named Undyne, for she was "undying".

Fire monsters were also severely lacking. As soon as humans had discovered that they were incredibly sensitive to water and ice, they then pursed the fiery villages and purged the poor monsters with torrential showers of water. One of the fire families had a young child named Grillby, who was about six years old. He was very quiet, but seemed to get along with everyone, including Papyrus. Gaster could have never been more proud of his son. Even with the recent death of his mother overshadowing them, Papyrus still put on a smile and tried his best to keep everyone he knew happy, including his father. He was quick to make friends with everyone, even if the others didn't exactly want to. He was just that lovable.

It continued like this for a while until every species of monster had relocated and reported back to the king. It was relieving to hear that some monsters had prospered in the war and had minimal casualties, but it really didn't make Gaster or the other sparse monsters any happier. Other monsters came in deathly sick or injured, and it was a challenge to round up the monsters who had healing magic to help, since a good number of those had either died or taken captive. Afterward, it was too confirmed that King Asgore and Queen Toriel were also the last of the royal goat monsters, too.

After every monster (or at least, every single one that could make it) had relocated to the king, Asgore decided that the rest of monsterkind should take refuge in the large caves situated under Mount Ebott. Not everyone was for this, but seeing that the humans were ruthless, it was a one-choice decision.

The humans were quick to follow the monsters, however. They managed to catch up with them just at the entrance of the underground caves. What was surprising, though, was that the humans didn't try to eradicate them all this time. A very important person that the humans called a "president" came with them to speak with King Asgore. The president seemed much kinder and more benevolent than the rest of the hateful humans, but he was also not perfect. He did, however, make a sort of deal called a "treaty" that stated that as long as monsters all remained below this mountain, the humans would call it a truce and stay away. Asgore, wanting nothing more than to help the rest of monsterkind, instantly agreed.

But this all came at a price. Seven human magicians were rounded up and placed at the entrance of the underground caverns. They used their magic to create a powerful barrier that no monster could pass. That way, monsters would always stay underground and never have the ability to leave at any time.

With the barrier created, the war on humans and monsters was officially forgotten. The humans went back down and minded their own business, and eventually all forgot that monsters even existed as they proceeded with their own lives. Mount Ebott became nothing more than a fabled myth as the years passed.

* * *

Although the barrier seemed impenetrable, Asgore quickly learned that the barrier could allow a monster through - but only if they carried a human soul with them. A human soul was about worth hundreds of times more than monster souls: they were more potent, and ran on determination. More research came about, and it was discovered that seven human souls could actually shatter the barrier, since seven magicians had created it!

The excitement about these news quickly died down as monsters realized that there was no way that they could get seven human souls. There were no humans in the newly-named Underground, and even if Asgore managed to extract every monster's soul, it would only amount to one human soul. And Asgore wasn't about to sacrifice everyone's lives just for that.

It was then decided by the king that, if one day, a human were to fall, any monster witness was to capture them and bring them to the Royal Guard, who would then take it to the king. The king would extract the soul of the human to collect seven. Just seven souls and the barrier could be shattered. It was clear that the monsters did not want to live down here, so they were willing to do as asked.

It took a while for Gaster to pull himself together, but with the help of his beloved son Papyrus, Gaster managed to break out of his morbid depression and continue living on. He dedicated his career to Soul Study; after meeting the king and showing him some of his studies, he at last achieved his dream to become a Royal Scientist. Asgore had been thoroughly impressed with his advanced work and research about human and monster souls, and was thus promoted. Gaster was invited to stay in the Capital, and would have readily accepted if it weren't for Papyrus. The big bustling city was no place for a young skeleton, who needed to learn and interact with other children his age.

Instead, Gaster made his home base in Snowdin, a quiet, cold place where everyone was friendly and knew each other. There were plenty of small monsters Papyrus could make friends with. Gaster built a custom laboratory in the basement of the large home he had acquired, and worked on everything there. About once a month, he would travel to the castle that Asgore now lived in to report any findings or inventions he had found or made. That way, it was much easier to spend time with his son.

As swimmingly as things were in this new world, however, Gaster quickly became apparent of something that was happening to Papyrus.


	4. Chapter 4 - Scientific Creation

Papyrus was lonely.

Sure, he had pulled through the death of his mother and was pretty much the most joyous child in the entire Underground, but Gaster knew his son better than anyone. The poor thing didn't have anyone he could truly call a friend.

The other monster children seemed to stick to their own kind. They didn't really want to include Papyrus, either because he was too "young" or too "different". It was true that Papyrus was happy, bright and naive, but that shouldn't have been a reason for the monsters to push him away. So who cares if the only food that Papyrus would talk about is spaghetti? Who cares if Papyrus didn't realize that monsters were insulting him and instead thought that they were complimenting him? In Gaster's eyes, he was a perfect skeleton with lots of potential. But not having any friends?

What made things worse was that Papyrus had been friends with the other little skeletons back when the village was still alive. He had been particularly fond of a few of them: Arial, T.N. Roman, and Tahoma. Now he had no one else of his own kind to talk to. Perhaps Undyne (the little guppy) would have been a good choice, but the captain of the Royal Guard lived in Waterfall, and that was a little way off.

Gaster couldn't bear to see his son in a state like this. He maximized the time he spent with him in hopes of making him happier, but it was getting vividly clear that Papyrus wanted another skeleton friend to play with, one he could share all his secrets and play with. None of the other children were so welcoming; so perhaps another skeleton child would suffice?

Sadly, there were no other skeleton monsters.

...

Or was that maybe not true?

* * *

It was a crazy thought. Completely delirious. Gaster was probably already out of his mind by thinking this.

But what if he could actually create another skeleton for Papyrus?

He had sufficient research done on monster souls and knew how they reproduced. He knew all about how souls functioned. So what if he created an artificial soul? He certainly had the lab equipment to do it; why not give it a shot?

Ludicrous, he thought. Unbelievable. It would never work like that.

But in his mind, he knew he wanted to try it out. Not only would this be the next biggest scientific discovery, it would mean Papyrus would finally have another skeleton friend to talk to.

It would also mean hundreds of hours of research and experimenting, but Gaster was willing to go through all that for his son.

It was set then. As crazy and asinine as the idea seemed, he would do it. He would create a soul.

* * *

Usually, monsters combined the essence of their souls to create a new one. Then the baby soul would stay with the mother (or the weakest monster, depending on the orientation of the couple) until its time was complete. Then the baby soul would separate from the mother and generate a new body, in which this would be called "birth". It was a very intimate process to combine souls, and often a long process for the baby soul to grow. That was about the dictionary definition of soul combining.

Gaster had no mate to combine with, and his soul was in now way suitable to hold an infant soul for a long time. Obviously, this meant he would have to create and incubate the soul differently once it was made. Easier said than done, however. Monster souls could not last very long outside their bodies. What if this same principle played out when attempting to incubate it?

 _I have to try_ , thought Gaster. _Anything for my son_.

With that notion set in mind, the Royal Scientist set out to build a suitable incubator to hold the soul in. He attached several panels and cables to it so that he would be able to read the stats while the soul was being developed. He wanted this child to be strong and healthy for Papyrus. The two would grow up together, having all the fun in the world. Then he used a portion of his magic to concoct a special type of embryonic fluid from various formulas that would act as the essence of the mother's soul. In human terms, he was building a womb. It took several tries to get the genetic makeup of the embryonic fluid to stay stable, but at last he did it. He made sure there was plenty of magic circulating the fluid.

Building the incubator alone and generating the fluid took about a few weeks, and it was all done at night, while his son was asleep. Gaster had stayed up late to read about soul magic and how to probably build a substitute soul incubator. It was tiring and bothersome, but he knew it'd be worth it in the long run.

And now...it was done. It was now time for the actual soul creation.

Gaster figured that taking a sliver of his own soul would be enough for his half. For the mother half...well, he did have something.

The tall skeleton turned and walked to a tall wardrobe and opened one of the drawers. He rifled through it until he found Calibri's old scarf, the one she wore when she was dusted. He had never cleansed the dust off it, but rather kept it a a reminder; just like humans would sometimes keep jars of their own fallen's dust. They called it ashes instead.

He took the scarf to a table and set up a tray. With bated breath, Gaster wrung the scarf and shook the dust onto the tray till it all accumulated into a small pile. Then he scooped up the dust and placed in in a test tube. This would serve as Calibri's half, as well as provide a genetic makeup for the soul's body.

"Okay... Time to do this. It's now or never," Gaster said to himself as he brought the test tube to the incubator, then flipped the machine on. He opened the lid of the incubator and made the sure the fluid was thoroughly stabilized before continuing.

After taking a few breaths to calm his nerves, he summoned forth his soul.

It was a sickly, pale thing; withered down by depression and constant use of magic. It still had a deep shade of purple, though, that marked his perseverance to continue on.

This was it. Gaster took another deep breath, took the soul in both hands, and tore a sliver from it.

 _Oh! Oh, damn, it was painful -!_

Gaster forced himself to stay on his toes as he held the small sliver in one hand while shoving his wounded soul back into his chest with the other.

 _This hurts, this hurts, oh, God..._

He had no time to shed tears, no time to scream. This had to be done now.

Gaster grabbed the test tube and poured all the dust onto the soul sliver. The tiny thing immediately started glowing and trembling. Then, he took it and placed it in the incubator, turning on the magic inducer. A warm purple glow started emanating with the fluid, filling the dusty soul with it. Then it changed from green to purple, then settled into a nice cyan blue and remained that way.

The soul sliver jerked around in the incubator, trying to stabilize by itself despite having no body to rely on. It seemed like an eternity to Gaster before the soul finally stopped trembling and instead started to grow. It kept expanding until it took the shape of a small, upside down cyan heart. Then it stood still, signifying that it had stabilized.

He did it.

He had created a new soul and it had lived through the conception.

Papyrus would finally have a friend to talk to.

Wait, no.

Not just a friend.

Papyrus would have a sibling.

Gaster couldn't help but grin ear to ear. He had finally done it. It had taken weeks to build the machine and the fluid, and while it only took a few minutes to actually generate the soul, it was extremely painful and had drained his HP significantly. But now Gaster was so overjoyed that he didn't mind the pain anymore. He had done it, he had done it! This was one of the best days of his life ever since they had come down here!

Gaster stepped back and sat down on the chair, exhaling slowly. He watched with joy at the tiny soul floating in the chamber. He could see from the readings chart that the soul's stats were normal and stable. This was good. This was perfect.

"And now the only thing left to do is watch you grow," Gaster whispered with pride.

* * *

The soul was growing quickly, to Gaster's delight.

Every night, after Papyrus had gone to bed, Gaster would head down to his lab and check on the little soul developing. He would check its stats and ensure that everything was alright, and he would occasionally drop a sprinkle of magic into the incubator to stimulate magic growth. Gaster wanted this child to be a strong, dependable sibling for Papyrus, one who would protect him and cherish him.

Another thing that amazed Gaster was that as time went on, the soul was able to connect to his own soul directly. He could sense whatever it was feeling. He assumed it was because he had used a piece of his own soul to create the child's, but it still mesmerized him in every way. The soul couldn't "speak" to him, so to say, but feelings like "curious", "happy", and things like that could be sent to him.

At the same time that feelings and consciousness was being developed, the body itself was also forming. No visible bones yet, but a translucent hazy structure was being formed around the small cyan heart. From the looks of it, this child would have a round head and a small body, but it was too soon to confirm anything yet. Gender was also undetermined yet, as well. For skeletons, gender was mainly determined by the shape of the pelvis. Girls had wider, shorter pelvises while boys' were longer and slightly narrower. Gaster knew humans' pelvises were also the same, but they did have fleshy parts of the body which was more commonly used to differentiate between gender. Since skeletons had none of that, it was mostly up to bone structure.

Gaster was just so giddy and excited about this. He couldn't wait for the soul to complete develop so that he could show it to Papyrus. He wondered how his son would react to it. Hopefully a good one.

Of course, he couldn't spend every single hour of his life on this project (though he kinda really wanted to). He still had his other scientific work for Asgore to do, and he surely wasn't about to neglect Papyrus. So he worked out a sort of schedule: Papyrus in the day, science work in the evening, soul in the night, and sleep whenever was feasible. It was not the best kind of schedule, but he would have to make do until then.

To be honest, it did hurt to leave the soul alone in the lab in fear that something might happen while he was gone, so Gaster thought of a solution. Though it was quite risky, he felt he had no other choice. Every night, once he either went to sleep or went back to Papyrus or work, he would take a test tube full of liquid determination and squeeze one drop into the incubator. This would stimulate the soul to keep going, so that it would be stronger and be alright by itself for longer periods of time. He made sure to not let more than one drop fall in; too much of it would make the soul melt and kill it. Gaster could not and _would not_ bear to see that. Determination was a tricky substance to use in monsters, but Gaster also felt that it would help this soul become the strongest it could. Maybe it would even be as determined as that one fish child Undyne is. No one could top that child's determination. It was as though she was born for the role (which she probably was).

Ahem. Anyway, back to the soul.

Gaster was tempted to name the soul himself (he had a few choice names) once gender was determined, but then he thought that he should let Papyrus name his new sibling. He felt it would be most fair. Whatever name Papyrus picked, he was sure it would be fine (unless it was something like "Ultra-Spaghetti-Master-Who-Is-Super-Cool").

* * *

As the weeks continued passing by, Gaster was elated to see that the bone structure was finally forming and solidifying. One look at its little pelvis bone and Gaster determined that he now had a second son. Oh, what fantastic news was this! He was so happy about this that he accidentally threw up the papers he had been holding onto the air in excitement. It took him a while to recollect everything into the right order, but he did not care. But he did have to keep quiet; he didn't want to wake up Papyrus, who was sleeping soundly at the time.

One thing he found oddly funny about the baby bones was his mouth. The teeth seemed to be quite large for his size, and if Gaster's eyesight had been any poorer, he could have said that it was arranged into a widespread smile.

Speaking of poor eyesight...

Gaster could really use some sleep. When was the last time he had slept for a full night? Probably weeks, from the looks of it. All this focus on the project at night had indeed taken its toll on his HP, dropping it down to slightly-concerning levels. He made a reminder to himself to eat something later.

Maybe...

Maybe he could sleep for a while. Everything was going fine with the baby bones; his stats were at a healthy 20 HP/DEF, and bone structure was coming along nicely. Though he was still growing and dependent, he was able to go longer periods of time without having to be constantly monitored. He was also requiring less and less doses of determination, so that was also a great sign.

Even as he was thinking all this, Gaster could feel his eyesockets growing heavy. Without thinking too clearly, he started putting his head down on the table he was sitting at. It probably wouldn't hurt to take a few moments to rest...

...

Gaster had only closed his eyes for about a few moments when he heard a small knocking at his door. Papyrus.

The tall skeleton immediately shot his head up. What on earth was his son doing up at this hour? Thinking quickly, he covered the incubator with a couple of sheets and went over to the door. He couldn't let Papyrus know about his new baby brother yet. It wasn't time.

"What is it, Papyrus? And why are you up this late?" Gaster asked as he opened the door and closed it behind him. "What happened?"

Papyrus fiddled a bit with the scarf that he had around his neck. "Someone's at the door and said they wanna talk with you," he said hesitantly. "He sounded important."

"Oh?" Gaster was honestly surprised. To come knocking by at this hour? It probably was very important.

"Alright, then. Go back to bed, I'll talk with whomever it is," Gaster said as he locked the lab doors.

Papyrus nodded and went back to his room. Gaster patted down his lab coat and made his way over to the door, wondering who it was and what message they had for him - oh.

"King Asgore?" Gaster's eyesockets opened wide. "Y-Your Majesty, is something the matter?"

The goat king looked incredibly frantic, yet he managed to keep a somewhat somber face. "Wing Dings, pardon me for intruding without having sent a message. I...I-I didn't know what to do, so I thought I would come and let you know, since you are my most trustworthy friend."

"Oh, sure, of course, Your Majesty," Gaster nodded. "But what happened?"

Kind Asgore cleared his throat before continuing. What he said next sent a ripple of shock through the tall skeleton's bones.

"A human has fallen into the Underground."


	5. Chapter 5 - Determination

Gaster felt his whole world slow down and stop when the king uttered those words.

A human had fallen into the Underground.

A human.

He didn't know what to feel. He had just gotten accustomed to this new life (and while it wasn't perfect, it was better than nothing), and he hadn't had to hear from those wretched beings ever since. And now, they dare to come crawling back?

Unknowingly, his hands curled up into fists and rattled softly. Why would Asgore tell him this, knowing that humans had caused the widespread death of his entire species? Knowing that these humans were the reason that Papyrus was motherless? Did Asgore really think he would just forgive them then and there simply because time had passed?

"... _Oh_ ," Gaster could only mumble in a low voice. He had so much to say, but he couldn't force himself to say it.

Asgore could see the look on Gaster's face and quickly corrected himself. "But this is different! They are not a human adult, like the ones from the war. This one is a child!"

A child? Now that got Gaster's attention. He didn't know much about human children; he had never really seen them during the war, or even before the war, actually. All he knew that human children were usually protected by their parents until they too became adults. But if a child fell here, where were its parents?

"But don't children usually have their parents looking after them? Why is this one alone?" Gaster couldn't help but ask.

"We do not know. Asriel found the human while out playing this afternoon. They were hurt, and he led them home to us. They are still resting as of now, but I thought I should come and tell you first."

Ahh, that's right. Asriel, the new Prince of the Underground. He had been borne to the king and queen some time after the war had ended. He was a happy, shy little goat kid, as far as everyone knew.

But now was not the time to dwell upon the prince. More pressing matters were at hand.

"...And what purpose would telling me serve?" Gaster asked warily, raising a nonexistent eyebrow.

Asgore sighed. "I know what the humans have done to your brethren, Wing Dings. I know what they did to mine, as well. But years have passed now, nearly a quarter of a century. I cannot bring myself to hurt this human, they most likely has never known anything about our kind. They are weak and injured right now, and..." here Asgore's voice cracked a little, "We were wondering if you could come and see the child yourself. You have knowledge of healing magic, but since your degree is soul study, we could also learn a bit more about how their human souls work."

"You want _me_ to heal the _human?_ " Gaster said incredulously. "Your Majesty, forgive me for speaking out of turn, but why me? My healing magic is clearly not the best; I only know so much. Why don't you ask another monster? Why don't you ask the Queen, surely she knows more than I!"

Asgore hesitated. "Tori's magic isn't the strongest, either, but it has helped. We're asking you because...well, you and the human share similar bone structure. The human might have broken limbs from the fall, so we thought that you of all monsters would know exactly what to fix."

Gaster pursed his nonexistent lips into a straight line. Sure, he knew everything there was to know about skeleton anatomy. But to use his healing magic on a human? It nearly felt like taboo and even betrayal to his fallen brethren. He would be helping the beings that had murdered his kin years ago.

But then again, the human was only a child. Surely, it didn't hold any knowledge of the war that had passed years ago. And Asgore was trusting him to do so. (Sure, he could just as easily force Gaster to do it, being King and all, but the goat was far too kind to issue a harsh command like that.)

Gaster let out a breath he didn't know he'd been holding. "...Alright," he said in a low voice. "I will assist the human, for now."

Asgore let out a hearty laugh full of relief. "Oh, thank heavens!" he said. "Quickly, then, there is no time to waste. You must come with me to the capital."

"Oh, but-" Gaster's mind suddenly went to the baby bones developing in his lab. He hadn't administered another drop of determination into the incubator. Would it be alright if he left it for longer...?

Asgore looked desperate. "Please, Wing Dings. I promise this won't take too long. Just heal the child and then you'll be able to return to your son."

Gaster looked extremely hesitant. He was all ready to pull away and make some excuse to go back into his house, but Asgore was already tugging on his arm, halfway down the road.

With a heavy sigh, Gaster let himself be dragged along. He sent a silent prayer to the stars that nothing would go wrong with his baby bones. Just stay put for a little bit, alright? It'll be okay.

It'll be okay.

* * *

The human child lay on Asriel's bed, its eyes shut and its chest rising and falling heavily. Queen Toriel had already gone ahead and bandaged up some of the most noticeable wounds on the child's body, but even from just looking, Gaster could tell that the child did indeed have some fractured limbs. Two fingers on its left hand, and its right ankle.

He honestly couldn't tell if this child was a girl or boy, because while it seemed to have a male body structure, it had long hair and pink rosy cheeks.

But never mind about that. Gaster was here for a reason.

A soft purple glow started flowing from his good eyesocket as he drifted over the human and placed his hands over theirs. His teeth chattered and clicked in his native tongue that was a special dialect known only to skeletons. Looking down at their hand, he used his magic to take the two fractured phalanges and bind them back together. He wasn't sure if this was painful to the child or not, because it didn't react. He then moved down and did the same thing to their ankle, binding the two fractured bones together and sealing it with a wave of healing magic.

As soon as he was sure it was done, he stopped flowing and stepped aside. "I believe the human is alright now," he said solemnly. "I recommend feeding it once it awakens to regain more of its HP back."

"Oh, thank you so much, Wing Dings!" Toriel suddenly cried with relief as she reached out and hugged Gaster tightly, who was surprised. Besides Papyrus, he wasn't too used to receiving hugs from anyone. "Thank you for helping the child!"

"I-It was no problem, really," Gaster felt himself mumble. Usually, using too much magic at once could take a toll on his health, but being older and more mature, it didn't really faze him as much as it should have.

As soon as Toriel released him, Gaster quickly patted his clothing down and looked at the goat parents. "So, what will happen once the child gets healthy? Will you take it back to the surface?"

Toriel and Asgore nervously eyed each other. Even before they could open their mouths, Gaster could tell that whatever they were going to say wasn't going to be good.

"It will be very hard for the child to leave," Asgore started quietly. "Sure, they have a human soul, but they also need to hold a monster soul before they could pass the barrier."

Gaster's eyes widened. "And you would sacrifice a monster's life in order to accomplish this?"

"We don't want anyone to give up their soul," Toriel quickly interjected. "Instead, we were thinking we could...um..."

Gaster couldn't believe it. "You want to _keep_ the human? Are you kidding me?"

"Peace, Wing Dings," Asgore quickly warned the scientist.

Toriel looked sheepish. "It seems like a selfish wish, I know. Hardly doable. But...I feel that we would be good parents for the child. They would be so lonely and afraid in this land. Wouldn't it be better if we could raise them as our own? They could be like a sibling to Asriel!"

"This...I..." Gaster was rendered speechless. "I-I don't think this is a good idea," he managed to say. "If you keep the human, its parents might come looking for it. They might blame us and then start a whole other war! Why don't you just take it to the surface?"

"Because we don't want to sacrifice anyone unless the wish is theirs," Asgore stated firmly. "We will keep and take care of the child until their parents come looking for them. Then we'll cross that bridge when we get to it."

Gaster was quiet. There was really no need to say anything else; the king and queen had made up their minds and once that happened, there was usually no going back.

"...Okay then," he said quietly and with as much politeness as he could muster. "Forgive me for speaking out, it was not my intention. I, uh...wish you good luck in raising the human."

Asgore's look softened. "It's alright, Wing Dings. Perhaps I should not have also been so coercive. But again, I thank you for helping the child."

"It's no problem," Gaster said, nodding his head. "I, um...must take my leave now, if you will. My son...he's waiting for me at home and I don't wish to worry him."

"Alright, Wing Dings, you may go now. Peace be with you," Asgore stated, waving lightly. "Say hello to Papyrus for me, won't you?"

Gaster quickly nodded before he turned and left the room as quickly as he could. His son was indeed waiting for him at home...but it wasn't Papyrus he had been referring to.

* * *

Gaster fumbled with the keys as he tried unlocking the door to his house. He was extremely anxious about the baby bones. He had been detained for longer than intended due to the talk he had with Asgore and Toriel, and now he wasn't sure how long the baby bones had gone without a drop of determination. Oh no, please be okay, please be okay...

As soon as the key for in the lock, he threw open the door and made a beeline straight for the lab. Hopefully, the ruckus he was making wouldn't wake Papyrus, but then again, the boy was a light sleeper.

His soul nearly jumped out of his chest as he saw that the space underneath the metal door shone a bright blue, and it was pulsing. Something was happening, oh no. Don't let anything happen, please.

Gaster quickly unlocked the door and ran inside, his eyes widening as he took in the sight.

The baby bones was still in the incubator, his tiny limbs wriggling about, but what alarmed Gaster was that the entire incubator was glowing a bright blue, turning the whole lab a shade of azure. The light permeated from the baby bones' soul, which was beating and throbbing as if it had tired itself out from using magic.

Magic.

Oh, dear.

Because the baby bones had gone so long without determination, he had started conjuring up his own magic in order to keep going. But now all this magic was taking its toll on the little one; the HP had dropped down to ten.

Thinking quickly, Gaster dashed to the table where he kept the vial of determination and pulled out an eye dropper. He opened the incubator and dropped a single drop of determination into the fluid, hoping he wasn't too late.

The baby bones suddenly jerked around and his soul fluttered again, but then he calmed down and the glow slowly dimmed. The stats panel went back to normal, although the HP was still at ten.

Gaster breathed a sigh of relief. The baby bones was alright. He was okay. He managed to survive for that long.

"You are indeed determined," he whispered breathlessly to the tiny skeleton. "You're gonna be the best brother ever for Papyrus."

A tentative knock was suddenly heard at the door. Gaster slowly looked up, knowing it was Papyrus who had probably awoken. He quickly covered the incubator with a sheet and then went to open the door.

"Daddy, are you alright?" the small child asked. "I heard a lotta running around and doors slamming."

"Oh, son, everything's alright," Gaster said with relief as he bent down and hugged Papyrus close, surprising the little one. "It's okay. Daddy just had to fix something in the lab really quick. But everything's alright, don't worry about it, okay?"

Everything's okay.


	6. Chapter 6 - New Life

It was nearly time.

Oh, Gaster was so excited about this! It had been a long couple of months of waiting for the baby bones to develop fully, about three months in earth time. It was three months of sleepless nights, sitting by the incubator and taking notes of the baby bones's development. It was three months of eager excitement. Sometimes, Gaster came so close to telling Papyrus the good news, but he knew that he had to wait. Just wait a little longer.

And now it was nearly time.

The skeleton's body was now fully developed, and now it was just a matter of time before the soul was fully charged and ready to be taken out. Then Papyrus would finally have his new baby brother.

The stats panel showed satisfactory stats: 100 HP/DEF/ATK and 100 in Magic Power Points (MPP). Though the baby seemed to have a small structure, he knew that this baby would definitely be strong and powerful; they would make a great sibling for Papyrus. The two of them would be able to grow up together and bond closely, and be able to protect one another.

Gaster had stopped giving the baby bones determination doses a while back. Ever since the stats had gone to 100, it had proven that the baby was more than capable of keeping himself alive. It would be alright now if he was left for long periods of time, like a week, for example.

Gaster sat back in his chair and lazily opened up a bag of popato chisps. They were his favorite snack, no matter how unhealthy Papyrus claimed they were. Technically, it was all he had been living on during nights like these. Sure, it hasn't given him too much energy, but hey, it kept him awake and alive. He wondered if the baby would enjoy eating them once he was able to. Papyrus would definitely have something to sag about that.

As he munched on the chisps, he listened to the weather outside. The last couple of days it had been quite rainy (or snowy, in Snowdin's case) and stormy. This night, however, the night had erupted into a full-on blizzard. It had gotten so bad that school had been cancelled for Papyrus, so the little one occupied his free time by eating spaghetti and building puzzles. He didn't know where on earth Papyrus found his love for making puzzles, but it had now almost completely invigorated him. Every day, he would come up to Gaster and present him with a new blueprint for a puzzle. Some were rather simple, while others were impossibly complicated. There was one that amused him, though: it was a tile puzzle that had different colors on it. Each color had a specific trait attributed to it. In order, Papyrus had explained it like this:

 _"You can't pass red tiles! Yellow tiles will zap you if you walk on it! Green tiles mean you have to play a mini game! Orange tiles make you smell like oranges! Blue tiles are water, so you can swim in them, but there are piranhas in there and they'll bite if you smell like oranges! And if a blue tile is next to a yellow one, it'll also zap you! Purple tiles are slippery and make you slip to the next tile! But the slippery soap is lemon-scented, which piranhas don't like! Purple and blue are okay! And the pink tiles...they don't do anything."_

Gaster had no idea how Papyrus was even able to think of a puzzle like this at his young age of only four, close to five, years old. But even he couldn't figure out the puzzle, no matter how many times he tried it. Yet Papyrus solved in several times on the first try. It just seemed easy for him.

He crunched on another chisp as he thought about these puzzles and potential solutions for them. He didn't hear the low moaning of a tree branch cracking and breaking from the strong winds and heavy snowfall. He didn't hear the crash that followed when the branch fell and severed the cords that powered the house.

All at once, the power cut out and the entire lab went pitch black.

Gaster nearly choked on the chisps as he fumbled to get out of his chair. Oh, no. _Oh, no._ This was bad, this was bad.

The incubator.

Suddenly, bubbling noises came from the incubator as the baby let out a frightened cry. Gaster could instantly see the tiny soul light up, filling the entire lab with a hazy light of bright blue.

As quickly as the lights fell out, the backup generator started working, and the power soon came back on. But the damage had been done.

The incubator wasn't working. It wouldn't turn on. It had stopped supporting the baby's vitals.

Gaster watched with horrified eyes as the stats panel came back on. Every single number was rapidly falling from 100, to 90, to 80...

"No, no, no!" he cried loudly as he realized what was happening. The baby was quickly dying in there. He had to get him out and save him. He could not bear to lose him after being so close.

He tried opening the incubator, but then he realized that it was sealed shut and wouldn't open unless turned on. This made him panic as he tried to force it open, but to no avail.

 _Save him, save him!_

Gaster could find no other way of opening it, so he grabbed a wrench from a lower drawer and smashed the glass open. Immediately, the fluid started flooding into a sticky pool of blue and purple into the floor. He broke away the glass, not caring that some shards embedded into his bones, then reached in and hurriedly took the baby out.

50, 40, 30...

The baby was out, but his stats were still falling. He was dying. His frightened cries quickly faded away and he lay limp in Gaster's arms, barely breathing. His soul started fading from blue to white.

 _Oh God, what can I do, what can I do?_

Gaster's eyes drifted over to the vial of determination on the table. That was it. He could literally inject the baby with the will to live. He would survive. He would live.

Running as fast as he could without slipping on the fluids, the scientist grabbed the vial with a free hand, as well as a syringe. It wouldn't take a lot. Just enough to save his baby from dusting. He couldn't bear to witness another skeleton die, especially one who hadn't even lived yet.

20, 15, 10...

He placed the baby on the table, then rapidly fumbled to get the needle into the vial.

9, 8, 7...

Gaster administrated the syringe, then went over and summoned the baby's soul out to him.

6, 5, 4...

His hands were trembling badly as he took the needle and injected the determination into the middle of the whitening soul.

3...2...1...

Suddenly, the baby jerked around on the table, his eyes opening wide to reveal two large empty sockets and his mouth opening to utter a silent cry. Gaster quickly picked him up from the table and held him tight.

The soul, looking so ready to fade into dust, trembled violently as it took in the determination. Its color jolted between red, blue and white as the determination swirled around and mixed with the soul.

 _Please live, please live..._

Then it all went quiet.

Gaster watched with bated breath as the baby's soul slowly started glowing a bright blue again before fading into the chest cavity, where all souls went when inactive. The baby closed its eyes and mouth, looking much calmer than before. Then, he opened his eyes again, but this time, two small white pupils emanated from the eye sockets and looked up at Gaster, gurgling quietly.

Gaster felt as if he would faint from relief. He had done it. The baby had taken the determination and lived. He would be okay now.

And now he was a father to two sons.

"Oh, welcome to the world, little one," Gaster whispered with a giant smile as he cuddled his son closely. "You're here now."

* * *

Gaster took some time to clean up the broken shards of glass and the fluid from the incubator and later put it all away. He wrapped the baby bones in cloths to keep him warm, then gently placed him on the table were the stats panel was. He needed to check the child's stats to see if anything could be done about the damage that had occurred to him. Taking some sensors, he clipped them to various places on the baby, then turned on the machine to see the results.

 **HP: 1/1**

 **DEF: 1/1**

 **ATK: 1/1**

 **MPP: 100/100**

Gaster thought his soul would crumble at seeing this. Every single stat except MPP had defaulted to 1. All the work he had gone through to increase the stats...gone. Now the baby wouldn't be as strong as he wanted him to be. One strike to the soul would instantly kill the poor thing. The only thing that stood out was the 100 stat for magic. So this meant that the child wouldn't constantly live in danger of dying, but also had a bountiful supply of magic. That had to amount to something, right?

Gaster sighed. All he wanted was the baby to be strong and powerful in every way. But now it seemed that he would be dependent for his entire life unless he gained LV, and that was definitely not going to happen.

He looked despondently at the baby as he nestled in the bundle. Then the baby opened his eyes once more and looked at Gaster, gurgling quietly and wriggling about. He looked mesmerized at seeing the world around him.

Such a beautiful baby he was...

Gaster quickly composed himself. What was he thinking? Sure, the baby's stats had diminished to nearly nothing, but he was alive and well. He would be a great brother to Papyrus, no matter what the stats were. He should be grateful that his baby son would live on. He should be grateful that he actually managed to create an artificial monster soul. That was unheard of, and would surely be brought out as the next biggest scientific discovery.

Gaster couldn't help himself as he quickly detached the cords from the baby, then picked up the tiny bundle and snuggled him closely.

"Would you like to meet your brother, little one?" he whispered happily.

The baby only made a few cooing sounds as he nestled in the bundle, but to Gaster; it was as if he could understand perfectly.

"Of course," he responded. "But I say it's getting rather late. Considering what you've been through, you definitely need rest. But don't worry, we'll meet your brother in the morning."

* * *

"Papyrus, come here, please!"

The small skeleton woke up upon hearing his dad's words. "Nyehhh?" he mumbled as he sat up in his racecar bed and stole a glance at the clock. It was nearly eight in the morning. Wow, he had really slept in that time.

Papyrus rubbed his sleepy eyes until he was fully awake, then climbed out of bed and went outside his room. "Where are you, Dad?" he yawned.

"I'm in the lab, son. Come here, please," the reply came.

The small skeleton quickly went down the stairs to the main floor, adjusting his beloved red scarf around his bony neck, then turned again to the door that had stairs leading down to the basement, or the lab, as his dad called it. He walked down the stairs, but then stopped at the metal door. Should he really go in? His dad always did say that it was not safe for him to go in, since there were big important machines inside that he should not touch.

"It's okay, Papyrus, you can come in this time," he heard his dad say.

Slightly nervous, Papyrus pushed aside the metal door and walked in. His eyes widened as he marveled at the lab that he had never seen before. There really were big machines everywhere, and it looked kinda like a school classroom, with lots of tables holding metal things with colorful glass tubes.

Gaster himself was standing in the middle of the room, his back to Papyrus. Walking closer, the small skeleton could tell that he was holding something in his arms, but he didn't know what.

"Dad? What is it?" he asked.

Gaster slowly turned around, an excited smile on his face. "I want to introduce you to someone," he said, barely able to contain his glee. He bent down and held out whatever was in his arms out. "Papyrus, meet your new baby brother."


	7. Chapter 7 - Hi, I'm Your New Brother

Papyrus's eyes nearly bugged out of his skull as he heard his dad's words.

What? A new baby brother? But, w-wasn't that impossible now? Where did he get-?

As he was thinking frantically about this, Papyrus looked down at the small bundle in his dad's arms and his train of thought completely derailed and crashed into stunned silence.

A tiny baby skeleton was wrapped snugly in the bundle. It had a round head and big eyes like his dad's, with tiny orbs of white light substituting as pupils. It had small mouth with lots of teeth, and if it could grin, it would be a wide smile. The baby looked up at Papyrus and let out a soft coo.

Papyrus couldn't help it; he fell in love with this tiny baby so quickly. "That's...my brother?" he gasped as he dropped to his knees, not quite sure if he was still dreaming. This had to be a dream, right? He wasn't able to get a brother now that his mama was gone...right?

He then looked up slowly at his dad, tears threatening to form in his eye sockets. "I-I have a brother...?"

Gaster thought his own grin couldn't get any wider on its own. "Yes, Papyrus, you have a baby brother now," he said, laughing a bit. "I had to wait quite a long time to make sure that everything was ready, but now he's here. He'll be the newest member of our family."

Papyrus couldn't believe his nonexistent ears. He had a brother! He finally had a brother to talk to and play with! He wasn't alone anymore! "Omigosh, a new brother! I have a brother now! Nyeh heh heh!" he cried joyously as he stood up again and jumped around happily. He felt his soul flutter with an excitement that he hadn't felt since he was a small baby himself. "This is the bestest day ever!" Then he looked up at his dad again, with a wide grin on his face. "What's his name?"

"Well, I had a few choices in mind, but then I thought that since he's your brother, you should get to name him," Gaster replied happily. "What do you think he should be called?"

Papyrus looked as if he would explode from happiness. "I get to name him?"

"Indeed you do. What should it be?"

The small skeleton went quiet as he thought of several choices for his brother. He remembered his friends, relatives and other skeletons that had lived back at the village. There were so many names that existed out there; which one would suit the baby best?

Papyrus's eyes suddenly widened as he thought of an idea. "Ooh! I have one!" he said excitedly. "What about Sans? Can we call him that?"

"Sans?" Gaster was genuinely surprised. Sans was an uncommon name for skeletons. Not many liked the typeface it held, for some reason; nor did they like the definition of the name, which was "without". Even he had a tough time remembering any skeleton from the village who might have shared the same name. So why that name?

"Why do you say 'Sans', Papyrus?"

"Because no one else is called Sans. So, _he_ should be called Sans!" Papyrus answered brightly, gesturing to the baby bones. "And "Sans" means "without", so "without" him, I wouldn't have a new baby brother!"

Gaster's eyes widened at the explanation. It seemed so simple, yet perfectly understandable. Then he smiled. "Alright, then, he shall be called Sans," he said, gently tapping the baby's skull. "Sans the Skeleton."

Sans let out a tiny coo as he looked up at Gaster, his eyes wide and curious. He tried to wriggle about, but he was too snugly wrapped in the blanket, so he settled with just stretching his little legs out.

* * *

Papyrus squealed with happiness. "Nyeh heh heh!" he laughed. "I shall be the best brother ever, and he shall also be my best brother ever!" Then he started to hold his arms out for his brother. "Lemme hold him, lemme hold him-"

"Wait, wait!" Gaster suddenly cried in alarm as he yanked Sans out of Papyrus's reach. "Don't touch him yet!"

Papyrus was stunned into silence by his father's outburst. "But...what? Why can't I hold him?" he asked, feeling confused and a little hurt. "I-I thought you said -"

Gaster pursed his lips together, realizing he had acted too strongly. "I-I'm sorry, Papyrus, for acting so brashly," he apologized. "Forgive me; I forgot to tell you something else about your brother, something very important. I need you to listen closely to me. Are you listening?"

Papyrus was quiet.

Gaster took a breath, then started explaining. "Right before Sans was born, something went wrong with the machine that kept him alive."

"He was born in a machine?" Papyrus interrupted unknowingly. He wondered how this process would have been done.

Gaster nodded. "Yes, he was. But the machine malfunctioned badly because the power cut out in the middle of the night. It severely affected all his stats, lowering all of them down to 1, minus MPP."

Papyrus couldn't believe what he was hearing. "S-So...Sans only has 1 HP?" he asked breathlessly. This was insane! Papyrus himself had 680 HP, and his dad 3000. But Sans only had 1?

"One HP, one DEF, and one ATK," Gaster affirmed. "He did keep his primary stat of MPP to 100, but that doesn't help him too much right now." He looked down at his oldest son. "Do you see what I am trying to tell you?"

Papyrus looked up at his father, then at his brother in his dad's arms. "Yeah. We gotta keep him safe, since he only has the one HP, right? We gotta protect him."

"That's right," Gaster said as he snuggled the baby close to him. "Until he learns to take care of himself, we'll need to watch over him and protect him. And even when he gets older, we may need to keep an eye on him. So I wanted to let you know that before you hold him. This isn't to say that I don't trust you; No, on the contrary, I completely trust you. I just...I-I just don't want to lose Sans so soon. Too much has happened, and I don't want to bear another loss."

Papyrus nodded solemnly. He didn't want to lose his baby brother so soon, either. He had just gotten to meet him! He wanted to grow up with Sans and be the bestest of brothers ever. "So...can I hold him now?" he asked tentatively. "I promise I won't hurt him."

"I know you won't, son," Gaster nodded. "But I just wanted to let you know beforehand in case anything happens." He then gently held out the little bundle to Papyrus, keeping his arms outstretched underneath, just in case.

Papyrus first sat down again, then reached out and carefully took Sans into his arms. It surprised him at how light he was for a baby. "Hiya, Sans," he said in a quieter tone, but his smile never ceased. "I'm your big brother, Papyrus. I promise I'm gonna take care of you and keep you safe, okay? I'll even teach you how to make spaghetti and do lots of puzzles!"

Sans had stopped wriggling about once Papyrus took him into his arms. He looked up at his brother with a curious expression and let out a few quiet babbles. Then he yawned and snuggled against Papyrus's chest before promptly falling asleep.

A bit alarmed, Papyrus looked up at his dad, who merely shrugged and laughed a little. "It's alright, son. Sans will sleep a lot throughout these first few weeks. It'll keep his HP high above its limit and keep him energized. Though...I _am_ surprised how quickly he fell asleep in your arms."

"Maybe it's because he knows I'm gonna be the best brother ever!" Papyrus grinned. He snuggled Sans closer to him, nearly able to feel his soul beating lightly. "Nyeh~..."

Gaster smiled warmly. "Heh, indeed. Who wouldn't love you, Papyrus?" he said as he reached out and gently rubbed the back of his older son's skull as an affectionate gesture.

* * *

The first few months were fairly easy enough. Gaster quickly went out to buy baby monster items at the Capital, since Papyrus had long outgrown all of his. Some monsters gave him odd looks, since they remembered that only he and his son remained as the last living skeletons, but Gaster kept his head high and walked on. He'd prove them all wrong eventually. But now wasn't the best time for confrontations.

Papyrus stayed home to take care of Sans, since no other monster knew about this, and frankly, Gaster didn't want to tell anyone yet. Besides, Papyrus had proved himself more than capable of taking care of Sans. Luckily, there were no incidents throughout those first few shopping days, since Sans only slept for the entire time. Whenever he woke up, Papyrus would smile and cuddle him, and occasionally give him a milk bottle to suckle on (it was the first thing that Gaster bought).

As soon as Gaster had bought all the necessary items, they set up Sans's room. They wanted to make sure that Sans would learn to sleep in his own room rather than becoming too dependent on them, so Gaster set up the spare room next to Papyrus's (his own room was in the lab). Gaster placed the crib and the various furniture in the corners, while Papyrus set up the toys and the mobile that hung over the crib. The mobile itself was a pretty thing; it had a cascade of glowing stars that twinkled softly.

As Gaster said, Sans spent most of his time sleeping, so there was little chance of danger. However, their sleep schedule was interrupted drastically because Sans tended to sleep only in the day, then wake up at night and demand attention. He would cry and cry until someone came to him and gave him what he wanted, which was usually a milk bottle. It was normally Gaster who tended to him, but sometimes Papyrus would instead go and cuddle Sans back to sleep.

Gaster tried to arrange Sans's schedule so that the baby bones would sleep at night instead, but it proved to be most difficult. Man, it had been such a long time since Papyrus himself was a baby, and even then, it had been Calibri who tended to him, so Gaster was basically out of practice. Maybe he should have thought this through better.

What Gaster thought was curiously interesting was that Sans would instantly fall asleep the moment he was in Papyrus's arms. Not matter what time it was or what the situation was, it was nap time for Sans whenever his brother held him. It seemed like a magical calming effect. Sans could be screaming and crying his head off, yet he would calm down and snooze once Papyrus came to him.

But of course, Gaster wouldn't force Papyrus to stay up all night so his brother could sleep. So, it was almost always Gaster who took care of Sans at night. But he could never replicate the sleeping effect quite as well as Papyrus could. Whenever Gaster held him, it took more work to get Sans to sleep.

* * *

Things went a little better once Sans learned to sleep at night. Gaster and Papyrus were free to sleep for the majority of the night, but Papyrus did tend to sneak in his brother's room and sleep beside him in the rocking chair. He wanted to make sure that absolutely nothing went wrong during the quiet hours.

Although things became better at night, it did start to get a little haphazard in the day once Sans learned how to crawl and generally became more active. Gaster and Papyrus quickly had to baby-proof the house, because Sans seemed to have a habit of wandering off and getting himself into trouble. He wasn't very active when it came to crawling itself (probably because of his low energy due to his HP), but for some reason, he always seemed to end up in the strangest of places. Gaster once found him sitting at the very top of the refrigerator, and Papyrus remembered seeing Sans trying to get into the trash can at one point.

But Sans was generally a very happy baby. He always had a wide, cute grin on his face, and was usually easily delighted by his father and brother. It didn't seem any harder to take care of Sans than it was to take care of another baby bones.

At least, that's what they thought.


	8. Chapter 8 - We All Fall Down

At first, it started out as a normal day. Gaster had finished giving the boys breakfast some time ago. Papyrus had his usual plate of spaghetti, and while he did try to feed Sans some of it, the baby bones didn't seem to take a real liking to it. Gaster himself only had a cup of strong coffee, much to the annoyance of his older son. Sure, it wasn't the most fitting nor nutritious breakfast, but at least it gave him energy and kept him from falling asleep right then and there.

He had been working more than usual lately for King Asgore. The king had fallen ill some time ago due to food poisoning or something similar and had been in bed for some time. He was feeling better now, but since he was still a little shaky, he requested more help. Gaster had assisted in creating some elixirs and other natural remedies to heal him, since Toriel's healing magic unaffected him for some strange reason. It was also very confusing that Gaster had to create multiple tonics to cure Asgore, rather than just needing one. He sometimes had to stay up late at night to complete the tonics, eating popato chisps to stay awake. He didn't care if it took a toll on his health; as long as his family was fine, he could afford to not care.

The good thing was that Sans was developing quite nicely. He had taken to crawling and he was able to smile and make more babbling noises. He had not learned how to walk or talk properly yet, but that was okay. It would take another couple of months, maybe even a year before he did so. Monsters often developed at a slower rate than humans. It helped prolong their life expectancy. Sans was still a very cheerful skeleton, and loved receiving attention from Gaster and Papyrus. Even though he didn't make an effort in doing much, Sans enjoyed having the two of them around to cater to him.

One thing that absolutely delighted Gaster was Papyrus. The older child's attitude had increased tenfold to a nearly euphoric state. It made Gaster so happy that Papyrus was back to his normal self; always talking and playing, without a care in the world.

Papyrus, unlike other skeletons, didn't seem to mind the fact that Sans often got a lot more attention. He genuinely embraced the fact that his baby brother had very low HP and knew that he needed a lot of care. Of course, Papyrus never wasted an opportunity to play games with Sans, whether it be playing with puzzles or imagining that they were superheroes of the Underground. And Sans? He would merely clap and giggle along, loving his brother's company. Gaster also thanked his lucky stars that Papyrus had not turned out to be a destructive child, or else there could have been an accident. The thought of losing Sans (or even Papyrus, for that matter) was simply too much to bear. Every night, Gaster would check Sans's stats, hoping that they would rise, but it turned out to be a bleak failure, for Sans stayed at his constant 1 HP/ATK/DEF. He was too young to have a magic induction (the term for when a young monster's magic is first activated in wild spurts), so there was no need to worry about that yet.

* * *

Gaster sipped his coffee as as watched Papyrus trying to spoon feed Sans some of his leftover spaghetti, who only smiled and pushed it away. Then he looked down at his watch. Hmm, if he delivered the tonics to Asgore today, they should arrive by next-

Gaster's train of thought suddenly derailed as a fierce knocking was heard at the front door. Papyrus looked up from trying to feed Sans, looking a bit alarmed. The last time someone had banged on the door like that, it was the king. What if it was this time, too...?

"I'll be right back, boys," Gaster said as he placed his cup down and briskly went to the door. He too remembered what had happened the last time someone rapped on the door with that much force and desperation.

Opening it, he was surprised to find not Asgore, but Toriel standing at his door. The queen clearly looked distraught, and she looked pale (which was saying something, considering that her fur was white).

"Oh, your Majesty?" Gaster's eyes widened. "Wh-What brings you here today?"

Without so much as a greeting, Toriel launched her dilemma at him. "Oh, Dr. Gaster, please come with us! We need your help immediately!"

Gaster quickly tugged his arm away, which was being pulled by Toriel. "Excuse me, your Majesty, but wh-what is the matter?"

Toriel looked ready to cry. "Oh, Dr. Gaster, it's our child, Chara!"

Chara? That must be the name of the human who had fallen to the Underground long ago. Strange name. "What's wrong with Chara?"

"We don't know! We think Chara might have accidentally consumed a pie filled with buttercups, and they've fallen very ill! They might be poisoned, and we need you to come over immediately!"

As quickly as Gaster had retracted his arm, Toriel had grabbed it again and was again trying to tug him out the door. "Please help! You would do the same for your son, wouldn't you?"

Gaster was confused by all this. Why did they keep soliciting him to help the human? He didn't know anything about it, he didn't even care if it lived or died. Humans were nothing but murderous, pathetic scum, the lot of them, and it would be better if they all dropped dead. At least then, monsters would live in peace.

But still...he couldn't refuse the queen like this. She looked like she was on the verge of a major breakdown. She considered the human to be her child...just like Gaster considered Sans to be his. And of course, he was willing to do anything for his sons, even if it meant sacrificing himself if a dire situation ever arose.

Sighing, he managed to turn his head around at Papyrus, who had left the table and had been standing behind him. "Papyrus, take care of everything for me, okay? I'll be right back," he instructed.

Papyrus gave a hesitant nod, wondering why the queen was acting so scared. Sans was still sitting at the kitchen table, curiously wondering why everyone had left.

Toriel wasted no time. Together, the two rapidly made their way towards New Home, where Asgore's domain rested.

* * *

Okay, Gaster wasn't about to lie. The human looked terrible.

It lay on the bed, its face nearly as pale as Gaster's bones. Long shaky gasps escaped its lips as it struggled to keep a hold on life. Its usually rosy cheeks were no more, and the long hair shrouded its face in obscurity, so Gaster still couldn't tell if the human was a male or female. Its face was drenched with sweat as it gasped softly. Beside the bed, Asriel sat on a chair, his little face scrunched up in worry and despair. His eyes were all red and puffy, signaling that he had been weeping for a long time. Asgore stood behind him, his face crestfallen and solemn.

Gaster was still unsure of this. "Okay, let's take a look," he mumbled to no one in particular as he activated his magic and summoned the human's soul forward.

...

Oh.

The soul was a sickly mess. It had lost all traces of color within, and was now a pale grey that throbbed gently. Hairline cracks covered the surface of it, and within every second, it lost more and more of its shine.

Gaster knew it was fruitless to inspect anywhere else. Whatever the human had ingested, it had proven to be fatal. It had fallen down - and once that happened, there was no going back. The complete loss of color was the telltale sign. The only reason why the brat probably hadn't died yet was because of its amount of determination. Humans always had a sickeningly high amount of that ready at their disposal. Gaster sometimes wondered how they didn't melt.

His mind returning to reality, the Royal Scientist cleared his throat as he summoned the pale soul back. Then he slowly turned to face the king and queen. "Your Majesties..." he solemnly began, knowing the next words would be heart-wrenching to the royals. "The human has fallen down."

* * *

There was a deafening silence that rang throughout the room. Then a collection of horrified gasps were bellowed out.

"No!" Toriel shouted in dismay as he then buried her face into her paws. "No, not Chara...!"

"O-Oh, my child!" Asgore cried out at the same time, tears bursting from his mellow eyes. "It can't be, Wingdings! S-Surely there must be a way to-"

Gaster gave two shakes of his head. "No, Asgore. Whatever the human are was severely detrimental to their well-being. Its soul has no color left. In fact, it probably should have died a few hours back, but its determination must have kept it alive till now. But now...I give the human only minutes left."

"No!" Toriel shouted again. Tears running down her face, she ran over and grabbed Gaster by the arms. "Please, Dr. Gaster! You can't just let up and let Chara die like that! Please, I beg of you, do som-"

Gaster quickly shook himself from her firm grasp, almost at the point of losing a few HP. "There's nothing I can do, your highness. Just as when we cannot help a fallen monster, we can't help a fallen human. Chara is going to die."

"Don't tell me that! My child can't die! They can't die...!" Toriel sobbed as Asgore came over and hugged her close to her chest.

Gaster tried to feel sorry for them, but he found it hard. He simply had no care for the human, no matter how sick it was. In response, he simply stood still and quiet, waiting for the human's soul to shatter. He noticed Asriel openly sobbing as he sat next to the bed, holding Chara's hands in his. The poor prince looked absolutely distraught at the thought of losing his adoptive sibling.

"Ch-Chara..." Asriel whimpered in a quiet whisper, barely audible over the sound of his parents weeping. "I'm sorry that I-I couldn't save you. I'm sorry...I knew I should've done something to help...but you know I'd do anything for you."

The white trembling soul rose again from the human's body, ready to depart from this realm. The human looked more and more close to death as the seconds ticked away.

Suddenly, a hoarse gasp grabbed everyone's attention. Toriel immediately turned from her husband's arms, while Asriel and Asgore's eyes widened. Even Gaster was surprised at this. At this point, the human was still determined to live?

"F...F-flowers..." it said, slowly turning to face Asriel. Strangely, it did not seem to acknowledge Toriel and Asgore in any way.

Asriel smiled and wiped some of his tears away. "Y-Yeah...flowers are pretty, right?"

"Flowers..." Chara repeated with more emphasis. Its eyes slowly drifted shut. "Want...to s-see...flowers..."

"You wanna see flowers? Which ones?" Asriel hurriedly said, wanting to please his sibling's last wish.

"V...vi...village flowers...surface..." Chara replied with a tiny, crackling voice before it went completely still. One last breath emanated from its lips, and then none more.

The human had died.


	9. Author's Note

**A/N: At long last, I return! :D**

 **I want to deeply apologize for leaving you all hanging on the various stories that I had here. D: I did not meant to disappear for so long, and I want to make up for it by continuing my work!**

 **Some of my stories will be heavily edited/updated to fix plot holes and general information, so please have patience with that. But I will now try to get into the swing of uploading things.**

 **(This chapter will be deleted once these stories are updated.)**


End file.
